Today is a transition day as a cold front pushes through the region. Behind the front we will see our coolest weather since Spring.

Today

Mild, Showers. Today will be cloudy and breezy as a cold front passes through the region. There will be just enough moisture associated with the front for some light showers. Chances of rain are 50/50. High temps will be around 77. Best chance of rain is during late morning through mid afternoon.

Clearing, Cooler. Tonight we will see partial clearing behind the front with freshening winds out of the north and northwest. Overnight temps will be chilly in the mid to upper 50s. Wednesday will be delightful with sunny skies and highs around 72.

Hurricane Gordon is weakening as it moves easterly toward southern Europe, and is obviously no factor for us. Hurricane Helene, like others before her, looks to recurve east of Bermuda and be no threat to the US. However, as Helene is still on a WNW trajectory, we are not totally out of the woods yet, and will continue to update as warranted.

Climatology Notes and El Nino

We are still almost 4 degrees below normal for September, and with a few below normal days this week, should remain in that range as we head into the home stretch. The last time DC had a September 4 degrees or more below average was 1963.

The National Weather Service's Climate Prediction Center issued a statement this past week declaring El Nino conditions in the Equatorial Pacific. This corroborated what we and many others have alluded to recently. El Nino is likely here through the winter. As we have mentioned earlier, this will have implications for our winter. At this time it is too early to say what the effect will be with any level of certainty.

Typically, weaker El Nino events have lead to colder and snowier conditions in the mid Atlantic. However, as the signal is weak, it can be overwhelmed by other indices/factors. Strong El Nino events have usually been warm and wet with very little snow. The last one of these was 1997-98, the strongest event on record. This upcoming event is most likely to be an in-between or moderate event. Some moderate El Nino's have led to cold and snowy winters, such as 2002-03. However, others such as 1994-95 were mostly warm with modest amounts of snow. The natural tendency is for moderate El Nino's to lean cold and snowy, but occasionally other factors are strong enough to offset/overwhelm its effect. Stay Tuned.

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This site is the archive for capitalweather.com, a website specializing in Washington DC weather, forecast, and climate information, actively maintained from 2004 through 2008. In 2008, we moved to the Washington Post and continued work as the Capital Weather Gang. You can find links to our current incarnation below. Thanks for browsing.